Plasma cells from patients with multiple myeloma will be isolated and injected into rabbits to produce antisera capable of recognizing antigen specific for plasma cell. Such antisera will be used in conjunction with the usual T and B cell surface markers to identify T, B and plasma cells in both normal bone marrow and in dysproteinemia bone marrows. The objective is to better understand and define the pathogenic relationship between B cells and neoplastic plasma cells and pathogenesis of B cell disorders. The immune response of humans to their myeloma plasma cells will be studied including cytotoxic antibodies, cytotoxic lymphocytes, antibody mediated lymohocyte toxicity, and "activated" macrophage cytolysis. Each patient will be studied repeatedly at 8 week intervals for 1-3 years and the relationship of their clinical studies, response to therapy and immune responses emphasized. The objective is to develop new insight into myeloma and develop new therapeutic strategies based on the above studies.